Various systems are available and used to manufacture sheets of paper and other sheet products. The sheets of material often have multiple characteristics that are monitored and controlled during the manufacturing process, such as dry weight, moisture, and caliper (thickness). The control of these or other sheet properties in a sheet-making machine is typically concerned with keeping the sheet properties as close as possible to target or desired values.
Sheet-making machines are often capable of producing sheets of material having different grades. For example, paper grades are typically associated with different characteristics of paper sheets. Some example types of paper grades include bond, book, label, and newsprint grades. Many sheet-making machines are also capable of transitioning from the production of one grade of material to the production of another grade of material in a continuous fashion. In other words, the sheet-making machines continue producing a sheet of material, but the grade of the sheet changes during the production. As a result, the sheet-making machines do not need to be shut down and restarted in order to change the grade of the sheet being produced.
In many instances, a grade change frequently results in production losses, meaning the sheet of material produced during the grade change is often unmarketable. This is typically due to the sheet having one or more undesirable characteristics, which are caused by altering the production process to change the grade of the sheet being produced. This typically results in a waste of material and a loss of revenue.